1. Field of the Invention
Aspects of the present invention relate to data encoding and decoding, and more particularly, to a method and apparatus to data encode and decode based on an error correction code (ECC) block, a storage medium having recorded thereon a program to implement the method, and a system to drive the storage medium.
2. Description of the Related Art
A system to drive a storage medium, such as a hard disk, a digital versatile disc (DVD), a high definition DVD (HD-DVD), or a Blu-ray disc, performs error correction code (ECC) block-based error correction for burst errors (such as physical scratches or fingerprints on the storage medium) or random errors (such as dust) during data decoding.
However, the performance of ECC block-based error correction of a conventional system to drive a storage medium is defined according to the type of the storage medium. For example, if the storage medium is a DVD, consecutive errors of a length corresponding to about 16 rows (16×182+10 bytes) of an ECC block can be corrected. For a HD-DVD, consecutive errors of a length corresponding to about 32 rows (32×182+10 bytes) of an ECC block can be corrected. For a Blu-ray disc, consecutive errors of a length corresponding to 64 rows (155×64 bytes) of an ECC block can be corrected. The physical length of consecutive errors that can be corrected can be set differently according to a recording density of a storage medium. For example, consecutive errors of approximately 6 mm for a DVD, consecutive errors of approximately 6.4 mm for an HD-DVD, and consecutive errors of approximately 9 mm for a Blu-ray disc can be corrected.
However, as the number of times the storage medium is used increases, degradation of data recorded thereon may occur due to recording or reproducing power and dust, scratches, and fingerprints resulting from management conditions of the storage medium. As a result, the probability that conventional standardized ECC block-based error correction fails increases. In particular, a physical scratch on the surface of the storage medium causes irreparable damage to data recorded thereon, increasing the probability that conventional standardized ECC block-based error correction fails. In the case of a failure in conventional standardized ECC block-based error correction, the reliability of data reproduced from the storage medium driving system decreases.
In an ECC block-based data communication system, the length of consecutive errors included in data may exceed the length of consecutive errors that can be corrected using an ECC block according to a condition like transmission speed. In this case, ECC-block based error correction fails in data decoding, causing transmission data loss. As a result, the reliability of data reproduced from the data communication system decreases.